Wake-modifying device for a boat

ABSTRACT

A recreational sport boat includes a hull, having starboard and port sides and a transom, and a pair of wake-modifying devices positioned aft of the transom. One of the wake-modifying devices is positioned on a port side of the boat&#39;s centerline and another of the wake-modifying devices is positioned on a starboard side of the boat&#39;s centerline. Each wake-modifying device includes a plate-like member and at least one downturned surface at a trailing portion of the plate-like member. Each wake-modifying device is pivotable between a non-deployed position and a deployed position about a pivot axis that is horizontal or inclined no more than about 35° from horizontal. When a wake-modifying device is in the deployed position, the downturned surface is lower than it is in the non-deployed position so as to be able to modify the boat&#39;s wake.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.14/922,451 filed Oct. 26, 2015. U.S. patent application Ser. No.14/922,451 is a continuation of U.S. patent application Ser. No.14/626,249 filed Feb. 19, 2015, now U.S. Pat. No. 9,174,703. U.S. patentapplication Ser. No. 14/626,249 is a continuation of U.S. patentapplication Ser. No. 14/458,427filed Aug. 13, 2014, now U.S. Pat. No.9,067,644. U.S. patent application Ser. No. 14/458,427is a continuationof U.S. patent application Ser. No. 14/194,355 filed Feb. 28, 2014, nowU.S. Pat. No. 8,833,286. U.S. patent application Ser. No. 14/194,355claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional PatentApplication No. 61/889,752, filed Oct. 11, 2013, and titled“Wake-Modifying Device for a Boat.” The foregoing applications arehereby incorporated by reference in their entireties and are made a partof this specification for all that they disclose.

FIELD OF THE INVENTION

The invention relates to a device for modifying the wake of a boat, aswell as a boat equipped with one or more such devices.

BACKGROUND OF THE INVENTION

Recreational sport boats are often used to tow water sports performerssuch as water skiers, wakeboarders, wake surfers, and the like. Theoptimal wake depends on which of these water sports a boat is used for,as well as the preferences and skill level of the performer. Waterskiers generally prefer a relatively smooth water surface, whilewakeboarders and wake surfers desire bigger wakes and wakes with moredefined shapes. In recent years, boats have been equipped with variousmeans for modifying the wake of the boat depending on how the boat isbeing used.

One example of a conventional means used to modify a boat's wake is atrim tab. Trim tabs originally were designed to adjust the trim of aboat. For example, when a boat is overloaded on the port side causingthe boat to list to port, a trim tab may be deployed on the port side tocause the boat to return to an even keel. More recently, trim tabs havebeen used to purposefully modify the wake of a boat. One way to do so isto use one or more trim tabs to lift the stern of the boat. Lifting thestern minimizes the wake of a boat, resulting in a relatively smoothwater surface, which is desirable for water skiing. Another way thattrim tabs have been used is to increase the displacement of one side ofthe boat, which increases the size of the wake on the side of the boatwith the increased displacement.

FIG. 1 shows the transom 122 of a boat used to tow a water sportsperformer. Three trim tabs 10, 20, 30 known in the art are mounted onthe transom 122: one on the port side, one at the centerline, and one onthe starboard side. Each tab is pivotably attached to the transom 122 ofthe boat by a hinge 11, 21, 31. The port and starboard trim tabs 10, 30are flat plates, with inboard and outboard edges bent upwards at a 90°angle. The upwardly-extending portion of each tab extends approximately¼ inch above the upper surface of the flat portion of the tabs. Thecenter trim tab 20 also is a flat plate, with inboard and outboard edgesbent downwards at a 90° angle and a trailing edge bent upwards at a 90°angle. The downwardly-extending portions of the center tab extendapproximately ⅛ inch below the lower surface of the flat portion of thetab, and the upwardly-extending portion extends approximately ¼ inchabove the upper surface of the flat portion. The edges of the trim tabs10, 20, 30 are bent upwards or downwards to aid in the manufacturingprocess and the extent to which the edges extend upwards or downwards ispreferably minimized.

Each of the aforementioned trim tabs 10, 20, 30 is pivotable between anon-deployed position and a deployed position. In FIG. 1, the port trimtab 10 is shown in a deployed position and the starboard trim tab 30 isshown in a non-deployed position. A linear actuator 510 moves each tabbetween the non-deployed position and the deployed position. As the boatmoves through the water, the water flowing under the boat impinges onthe deployed trim tab, creating an upward force on the tab. As a result,the portion of the boat where the trim tab is attached is raised. Whenused for water skiing, the center tab 20 may be deployed to raise theentire stern of the boat and minimize the wake. To increase the wake ofthe boat for wake surfing, either one of the port or starboard trim tabsmay be deployed. When the port trim tab 10 is deployed, for example, theport side of the boat is raised, causing an increase in displacement onthe starboard side of the boat, which increases the size of thestarboard wake. The side of the boat with the increased wake is the surfside, which, in this example, is the starboard side. To further increasethe size of the wake, ballast may also be added to the surf side of theboat.

In the embodiment shown in FIGS. 1 and 2, the port and starboard trimtabs 10, 30 are not perfectly rectangular, but rather have an angledcontour along their outboard edges. This is so that the trim tabs do notextend beyond the outer perimeter of a swim platform (not shown) mountedto the transom 122 of the boat, above the trim tabs 10, 20, 30.Alternatively, all of the trim tabs may have a rectangular shape.

Even with the trim tabs described above, wakeboarders and wake surfersdesire larger wakes with improved shapes. For surfing in particular,wake surfers desire a wake with a large surfable area. The surfable areais the portion of the wake that pushes the surfer forward. This areagenerally extends from the curl of the wake to the swim platform.

SUMMARY OF THE INVENTION

In one aspect, the invention relates to a wake-modifying device adaptedto be attached to a boat, aft of the boat's transom, on either a port orstarboard side of the boat's centerline.

In another aspect, the invention relates to a recreational sport boatincluding a hull, having starboard and port sides and a transom, and apair of wake-modifying devices positioned aft of the transom. One of thewake-modifying devices is positioned on a port side of the boat'scenterline and another of the wake-modifying devices is positioned on astarboard side of the boat's centerline. Preferably, each wake-modifyingdevice is pivotably attached directly to the transom. Alternatively, oneor both of the wake-modifying devices may be attached to other portionsof the boat, such as the bottom or sides of the hull or a swim platform.

Each wake-modifying device includes a plate-like member and at least onedownturned surface at a trailing portion of the plate-like member. Eachwake-modifying device is pivotable between a non-deployed position and adeployed position about a pivot axis that is horizontal or inclined nomore than about 35° from horizontal. In the deployed position, thedownturned surface is lower than it is in the non-deployed position soas to be able to modify the boat's wake.

The plate-like member and the downturned surface of each wake-modifyingdevice may be an integral piece or separate pieces joined together. Thedownturned surface may be at a trailing edge of the plate-like member,for example, when they are an integral piece. Or the downturned surfacemay be inward of the trailing edge, for example, when the downturnedsurface is a separate piece attached to a lower surface of theplate-like member.

Preferably, an angle between the downturned surface of eachwake-modifying device and a lower surface of a central portion of theplate-like member is between about 120° to about 135°, and thedownturned surface extends between about 1 inch to about 2¼ inches belowthe lower surface of the plate-like member. The downturned surface maybe oriented such that it intersects the plate-like member along a linethat is generally parallel to the pivot axis, or along a line that is atan oblique angle relative to the pivot axis. The downturned surface andthe plate-like member need not intersect along a straight line, and mayinstead intersect along a curved line.

Preferably, each wake-modifying device includes not one but two (ormore) downturned surfaces at a trailing portion of the plate-likemember. A first one of the downturned surfaces may intersect theplate-like member along a line that is generally parallel to the pivotaxis, and a second one of the downturned surfaces may intersect theplate-like member along a line that is at an obtuse angle relative tothe line along which the first downturned surface and the plate-likemember intersect. Preferably, the obtuse angle is between about 135° toabout 150°, and the first downturned surface is outboard of the seconddownturned surface.

Each wake-modifying device may also include at least one upturnedsurface at an outboard portion of the plate-like member, between thedownturned surface and the pivot axis. The plate-like member and theupturned surface may be an integral piece or separate pieces joinedtogether, and the upturned surface may be at an outboard edge of theplate-like member or inward of the outboard edge. An angle between theupturned surface and an upper surface of a central portion of theplate-like member preferably is between about 30° to about 150°, andmore preferably is about 90°. The upturned surface preferably extends atleast about 1 inch above an upper surface of the plate-like member.

At least one of the wake-modifying devices may include anotherdownturned surface at an inboard portion of the plate-like member,between the first downturned surface and the pivot axis. An anglebetween this downturned surface and the lower surface of a centralportion of the plate-like member preferably is between about 30° toabout 150°, and more preferably is about 90°. The plate-like member andthis downturned surface may be an integral piece or separate piecesjoined together, and the downturned surface may be at an inboard edge ofthe plate-like member or inward of the inboard edge.

At least one of the wake-modifying devices may also include at least onefin attached to the lower surface of the plate-like member. An anglebetween the fin and the lower surface of the plate-like memberpreferably is between about 30° to about 150°, and more preferably isabout 90°. The fin preferably extends at least about 1 inch below thelower surface of the plate-like member. The fin and the plate-likemember preferably intersect along a line that is at an angle betweenabout 15° and about 75° relative to the pivot axis, and more preferablybetween about 30° and about 60° relative to the pivot axis, and extendsin a direction aft and outboard from the pivot axis. In some cases, itmay be desirable to have at least two fins, which preferably areparallel to each other.

Each wake-modifying device preferably is capable of assuming multipledeployed positions. In each different deployed position thewake-modifying device is pivoted downwardly at a different anglerelative to the non-deployed position. The boat may include a pair oflinear actuators, each operable to move a respective one of thewake-modifying devices between its non-deployed position and itsdeployed position. The boat also preferably includes an operator stationwith a controller configured to control the operation of each linearactuator.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a transom of a boat equipped with prior art trim tabs.

FIG. 2 is a detailed view the starboard trim tab shown in FIG. 1.

FIG. 3 shows a boat including a pair of wake-modifying devices accordingto a first preferred embodiment of the invention.

FIG. 4 is a stern view of the boat shown in FIG. 3.

FIG. 5A is a detailed view of the port wake-modifying device shown inFIG. 3.

FIG. 5B shows an alternate orientation of a wake-modifying device.

FIG. 6 is a detailed view of the bottom of the port wake-modifyingdevice shown in FIG. 3.

FIG. 7 is a perspective view of the port wake-modifying device shown inFIG. 3, detached from the boat and shown here from the inboard side.

FIG. 8 is a perspective view of the port wake-modifying device shown inFIG. 7, shown here from the outboard side.

FIG. 9 is a perspective view of the port wake-modifying device shown inFIG. 7, turned upside down and shown here from the outboard side.

FIG. 10 is an outboard elevation view of the port wake-modifying deviceshown in FIG. 7.

FIG. 11 is an inboard elevation view of the port wake-modifying deviceshown in FIG. 7.

FIG. 12 is an aft elevation view of the port wake-modifying device shownin FIG. 7.

FIG. 13 is a top elevation view of the port wake-modifying device shownin FIG. 7.

FIG. 14 is a foreside elevation view of the port wake-modifying deviceshown in FIG. 7.

FIG. 15 is a bottom elevation view of the port wake-modifying deviceshown in FIG. 7.

FIG. 16 is a port side view of the boat shown in FIG. 3, with the portwake-modifying device in a non-deployed position.

FIG. 17 is a port side view of the boat shown in FIG. 3, with the portwake-modifying device in a deployed position.

FIG. 18 is a manufacturing view of the port wake-modifying device shownin FIG. 7.

FIG. 19 is a perspective view of the starboard wake-modifying deviceshown in FIG. 3, detached from the boat and shown here from the outboardside.

FIG. 20 is a perspective view of the starboard wake-modifying deviceshown in FIG. 19, shown here from the inboard side.

FIG. 21 is a perspective view of the starboard wake-modifying deviceshown in FIG. 19, turned upside down and shown here from the outboardside.

FIG. 22 is an inboard elevation view of the starboard wake-modifyingdevice shown in FIG. 19.

FIG. 23 is an outboard elevation view of the starboard wake-modifyingdevice shown in FIG. 19.

FIG. 24 is an aft elevation view of the starboard wake-modifying deviceshown in FIG. 19.

FIG. 25 is a top elevation view of the starboard wake-modifying deviceshown in FIG. 19.

FIG. 26 is a foreside elevation view of the starboard wake-modifyingdevice shown in FIG. 19.

FIG. 27 is a bottom elevation view of the starboard wake-modifyingdevice shown in FIG. 19.

FIG. 28 is a starboard side view of the boat shown in FIG. 3, with thestarboard wake-modifying device in a non-deployed position.

FIG. 29 is a starboard side view of the boat shown in FIG. 3, with thestarboard wake-modifying device in a deployed position.

FIG. 30 is a manufacturing view of the starboard wake-modifying deviceshown in FIG. 19.

FIG. 31 is a stern view of a boat including a pair of wake-modifyingdevices according to a second preferred embodiment of the invention.

FIG. 32 is a detailed view of the port wake-modifying device shown inFIG. 31.

FIG. 33 is a detailed view of the bottom of the port wake-modifyingdevice shown in FIG. 31.

FIG. 34 is a perspective view of the port wake-modifying device shown inFIG. 31, detached from the boat and shown here from the inboard side.

FIG. 35 is a perspective view of the port wake-modifying device shown inFIG. 34, shown here from the outboard side.

FIG. 36 is a perspective view of the port wake-modifying device shown inFIG. 34, turned upside down and shown here from the outboard side.

FIG. 37 is an outboard elevation view of the port wake-modifying deviceshown in FIG. 34.

FIG. 38 is an inboard elevation view of the port wake-modifying deviceshown in FIG. 34.

FIG. 39 is an aft elevation view of the port wake-modifying device shownin FIG. 34.

FIG. 40 is a top elevation view of the port wake-modifying device shownin FIG. 34.

FIG. 41 is a foreside elevation view of the port wake-modifying deviceshown in FIG. 34.

FIG. 42 is a bottom elevation view of the port wake-modifying deviceshown in FIG. 34.

FIG. 43 is a port side view of the boat shown in FIG. 31, with the portwake-modifying device in a non-deployed position.

FIG. 44 is a port side view of the boat shown in FIG. 31, with the portwake-modifying device in a deployed position.

FIG. 45 is a manufacturing view of the port wake-modifying device shownin FIG. 34.

FIG. 46 is a perspective view of the starboard wake-modifying deviceshown in FIG. 31, detached from the boat and shown here from theoutboard side.

FIG. 47 is a perspective view of the starboard wake-modifying deviceshown in FIG. 46, shown here from the inboard side.

FIG. 48 is a perspective view of the starboard wake-modifying deviceshown in FIG. 46, turned upside down and shown here from the outboardside.

FIG. 49 is an inboard elevation view of the starboard wake-modifyingdevice shown in FIG. 46.

FIG. 50 is an outboard elevation view of the starboard wake-modifyingdevice shown in FIG. 46.

FIG. 51 is an aft elevation view of the starboard wake-modifying deviceshown in FIG. 46.

FIG. 52 is a top elevation view of the starboard wake-modifying deviceshown in FIG. 46.

FIG. 53 is a foreside elevation view of the starboard wake-modifyingdevice shown in FIG. 46.

FIG. 54 is a bottom elevation view of the starboard wake-modifyingdevice shown in FIG. 46.

FIG. 55 is a starboard side view of the boat shown in FIG. 31, with thestarboard wake-modifying device in a non-deployed position.

FIG. 56 is a starboard side view of the boat shown in FIG. 31, with thestarboard wake-modifying device in a deployed position.

FIG. 57 is a manufacturing view of the starboard wake-modifying deviceshown in FIG. 46.

FIG. 58 is a stern view of a boat including a pair of wake-modifyingdevices according to a third preferred embodiment of the invention.

FIG. 59 is a detailed view of the port wake-modifying device shown inFIG. 58.

FIG. 60 is a detailed view of the bottom of the port wake-modifyingdevice shown in FIG. 58.

FIG. 61 is a perspective view of the port wake-modifying device shown inFIG. 58, detached from the boat and shown here from the inboard side.

FIG. 62 is a perspective view of the port wake-modifying device shown inFIG. 61, shown here from the outboard side.

FIG. 63 is a perspective view of the port wake-modifying device shown inFIG. 61, turned upside down and shown here from the outboard side.

FIG. 64 is an outboard elevation view of the port wake-modifying deviceshown in FIG. 61.

FIG. 65 is an inboard elevation view of the port wake-modifying deviceshown in FIG. 61.

FIG. 66 is an aft elevation view of the port wake-modifying device shownin FIG. 61.

FIG. 67 is a top elevation view of the port wake-modifying device shownin FIG. 61.

FIG. 68 is a foreside elevation view of the port wake-modifying deviceshown in FIG. 61.

FIG. 69 is a bottom elevation view of the port wake-modifying deviceshown in FIG. 61.

FIG. 70 is a port side view of the boat shown in FIG. 58, with the portwake-modifying device in a non-deployed position.

FIG. 71 is a port side view of the boat shown in FIG. 58, with the portwake-modifying device in a deployed position.

FIG. 72 is a manufacturing view of the port wake-modifying device shownin FIG. 61.

FIG. 73 is a perspective view of the starboard wake-modifying deviceshown in FIG. 58, detached from the boat and shown here from theoutboard side.

FIG. 74 is a perspective view of the starboard wake-modifying deviceshown in FIG. 73, shown here from the inboard side.

FIG. 75 is a perspective view of the starboard wake-modifying deviceshown in FIG. 73, turned upside down and shown here from the outboardside.

FIG. 76 is an inboard elevation view of the starboard wake-modifyingdevice shown in FIG. 73.

FIG. 77 is an outboard elevation view of the starboard wake-modifyingdevice shown in FIG. 73.

FIG. 78 is an aft elevation view of the starboard wake-modifying deviceshown in FIG. 73.

FIG. 79 is a top elevation view of the starboard wake-modifying deviceshown in FIG. 73.

FIG. 80 is a foreside elevation view of the starboard wake-modifyingdevice shown in FIG. 73.

FIG. 81 is a bottom elevation view of the starboard wake-modifyingdevice shown in FIG. 73.

FIG. 82 is a starboard side view of the boat shown in FIG. 58, with thestarboard wake-modifying device in a non-deployed position.

FIG. 83 is a starboard side view of the boat shown in FIG. 58, with thestarboard wake-modifying device in a deployed position.

FIG. 84 is a manufacturing view of the starboard wake-modifying deviceshown in FIG. 73.

FIG. 85 shows an exemplary control screen for operating thewake-modifying devices shown in the previous figures.

FIG. 86 shows an edit screen accessed from the control screen shown inFIG. 85.

FIG. 87 shows another exemplary control screen for operating thewake-modifying devices shown in the previous figures.

FIG. 88 shows a selection screen accessed from the control screen shownin FIG. 87.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Exemplary preferred embodiments of the invention will now be describedwith reference to the accompanying figures. Like reference numeralsrefer to the same or similar elements throughout the figures anddescription.

First Embodiment

FIGS. 3 and 4 show a boat 100 equipped with a pair of wake-modifyingdevices 111, 112 in accordance with a first preferred embodiment of theinvention. The boat hull 120 includes a bow 121, a transom 122, and portand starboard sides 123, 124. Within the boat's interior is a controlconsole 140 for operating the boat 100. The boat 100 is driven by asingle inboard motor (not shown) connected to a left-handed propeller170. However, the wake-modifying devices 111, 112 can be utilized withother types of boats and propulsion systems, including but not limitedto right-handed propellers, outboard motors, sterndrives, and the like.

The boat 100 has a centerline 150 running down the center of the boat,halfway between the port and starboard sides 123, 124. A conventionaltrim tab 20 is pivotably attached to the transom 122 along thecenterline 150. The wake-modifying devices 111, 112 are pivotablyattached to the transom 122 on port and starboard sides of thecenterline 150, respectively.

FIGS. 5-18 are detailed views of the wake-modifying device 111 on theport side of the boat 100. Similarly, FIGS. 19-30 are detailed views ofthe wake-modifying device 112 on the starboard side of the boat 100.While the port and starboard wake modifying-devices 111, 112 have manysimilar features in this embodiment, the port and starboardwake-modifying devices 111, 112 differ with respect to one downturnedsurface 330, which the port wake-modifying device 111 includes and thestarboard wake-modifying device 112 lacks, as will be discussed furtherbelow. Except where noted otherwise, the discussion of thewake-modifying devices applies equally to both the port and starboardwake-modifying devices 111, 112.

Each wake-modifying device 111, 112 includes a plate-like member 200that is pivotably attached to the transom 122 of the boat 100. Theplate-like member 200 pivots about a pivot axis 210 to move between anon-deployed position and a deployed position. In this embodiment, thepivot axis 210 is a hinge and is flush with the transom 122 of the boat100. Here, the hinge is a piano hinge that is welded to a leadingportion L of the plate-like member 200 and attached to the transom ofthe boat 100 using screws. However, any suitable pivotable connectionmay be used and it may be affixed to the wake-modifying device 111, 112and transom 122 of the boat 100 using any suitable means, including butnot limited to bolts, screws, rivets, welding, and epoxy. In addition,the wake-modifying device 111, 112 may be attached to the transom 122such that the pivot axis 210 is not flush with the transom 122, forexample, the pivot axis may be spaced further aft of the transom 122, asshown, for example, in FIG. 5B. The wake-modifying devices 111, 112 alsomay be attached to portions of the boat other than the transom 122. Forexample, the wake-modifying devices 111, 112 could be attached to thebottom of the hull 120, to the port and starboard sides 123, 124 of thehull 120, or to a swim platform (not shown). The pivot axis 210preferably is parallel to the transom 122, but it may be oriented at anoblique angle τ relative to the transom 122, as shown, for example, inFIG. 5B, so long as the wake-modifying device 111, 112 provides anupward force on the boat 100 as the boat 100 travels forward through thewater.

In the embodiment shown, the pivot axis 210 is parallel to the deadrise(the angle of the hull from the keel to the chine at the transom 122) ofthe boat 100. But the pivot axis 210 may instead be at an angle relativeto the deadrise. Some boats, for example, have little or no deadrise. Insuch cases, it may be advantageous to orient the pivot axis 210 at anangle relative to the deadrise. Preferably, the pivot axis is inclinedno more than about 35° from horizontal, more preferably no more thanabout 20° from horizontal, and most preferably no more than about 15°from horizontal. This inclination is preferably in the direction fromthe chine to the keel. Preferably, the pivot axis is inclined no morethan about 15° more than the deadrise.

The plate-like member 200 has a trailing portion T that is aft of theleading portion L. The trailing portion T is the aft half of theplate-like member 200, and the leading portion L is the forward half ofthe plate-like member 200. The plate-like member 200 also has an inboardportion I and an outboard portion O. The inboard portion I is theinboard half of the plate-like member, and the outboard portion O is theoutboard half of the plate-like member. Thus, the plate-like member maybe divided into quadrants as shown in FIGS. 13 and 25: a leading,inboard portion L, I; a leading, outboard portion L, O; a trailing,inboard portion T, I; and a trailing, outboard portion T, O.

In the embodiment shown, there are two downturned surfaces 310, 320 atthe trailing portion T of the plate-like member 200. The firstdownturned surface 310 intersects the plate-like member 200 along a linethat is generally parallel to the pivot axis 210. The second downturnedsurface 320 intersects the plate-like member 200 along a line that isoriented at an angle α relative to the pivot axis 210. In thisembodiment, the first downturned surface 310 is outboard of the seconddownturned surface 320, which is at the trailing, inboard portion T, Iof the plate-like member 200. The second downturned surface 320 mayextend into adjacent quadrants without deviating from the scope of theinvention. The first and second downturned surfaces 310, 320 preferablyare at the edge of the plate-like member 200, but they may be inward ofthe edge.

The inventors believe that the combination of the plate-like member 200and one or both of the downturned surfaces 310, 320 improves the sizeand shape of the wake. The side of the boat 100 with the desirable wakeis referred to as the surf side. The surf side is the side of the boat100 opposite a deployed wake-modifying device. The side with thedeployed wake-modifying device is referred to as the non-surf side.

As the boat 100 moves through the water, the hull displaces water bothdownward under the hull 120 and outward of the sides 123, 124 of thehull 120. This creates a cavity immediately behind the boat 100. Thedisplaced water recovers behind the boat 100 to fill the cavity. As thedisplaced water recovers, the water converges from under the boat 100and from the sides 123, 124 of the hull 120. When the convergence occurswith sufficient force, it creates a v-shaped wave crest or “roostertail” at the point of convergence. This v-shaped crest then propagatesoutward behind the boat 100 creating a wake that is suitable forwakeboarding, wake surfing, and the like. When one of the wake-modifyingdevices 111, 112 is in the deployed position, the downturned surfaces310, 320 direct the water sharply downward. This sharp redirection ofwater results in an additional upward force to roll the boat 100 towardthe surf side to a greater degree than the prior art trim tabs discussedabove and shown in FIGS. 1 and 2. As a result, the boat 100 displacesmore water on the surf side creating a more desirable wake for surfing.The inventors have found that shifting the point of convergence aft ofthe transom 122 and toward the non-surf side will also improve the wakeon the surf side. The inventors believe that creating a trough in thewater behind the deployed wake-modifying device and delaying the waterfrom recovering from the non-surf side shifts the convergence point aftof the transom 122 and toward the non-surf side. The downturned surfaces310, 320 are believed to contribute to both of these actions. The anglesof the downturned surfaces and the size of the plate contribute to thetiming of water recovery to increase the size of the wake on the surfside as a result of wave superposition.

The downturned surface 310, 320 should extend far enough in a downwarddirection to cause redirection of the water. The downturned surface 310,320 should also be short enough that the downturned surface does notinteract with the water when in the non-deployed position. Preferably,the downturned surface 310, 320 extends from about 1 inch to about 2¼inches below a lower surface 220 of the plate-like member 200, and morepreferably about 1½ inches below the lower surface 220 of the plate-likemember 200. The downturned surface 310, 320 forms an angle β with alower surface 220 of a central portion of the plate-like member 200. Theinventors have found that this angle β should be sufficient to redirectthe water, but not so sharp as to result in excessive force on thewake-modifying device 111, 112. Preferably, the angle β between thedownturned surface 310, 320 the lower surface 220 of the central portionof the plate-like member 200 is between about 120° and about 135°.

The water converging behind the boat 100 from the sides 123, 124 of thehull 120 forms an angle with the sides of the hull 123, 124. Theinventors have found that orienting a downturned surface 320 tointersect this angle improves the wake on the surf side. Accordingly,the line where the second downturned surface 320 intersects theplate-like member 200 is oriented at an angle α relative to the pivotaxis 210. This angle α preferably is perpendicular to the angle formedbetween the recovering water and the side 123, 124 of the hull 120. Theangle α preferably is between about 30° to about 45°.

In the embodiment shown, the wake-modifying device 111, 112 has twoupturned surfaces 410, 420 between the first downturned surface 310 andthe pivot axis 210. These upturned surfaces 410, 420 are at the outboardportion O of the plate-like member 200, preferably at the edge of theplate-like member, but they may be inward of the edge. An angle γbetween the upturned surfaces 410, 420 and an upper surface 230 of thecentral portion of the plate-like member 200 preferably is between about30° to about 150°, and more preferably is about 90°. The inventorsbelieve that these upturned surfaces 410, 420 delay the water on thenon-surf side from converging behind the boat 100 and further shift thepoint of convergence aft of the transom 122 and toward the non-surfside. The upturned surfaces 410, 420 should extend far enough in anupward direction to delay the water. The upturned surfaces 410, 420preferably extend at least about 1 inch above the upper surface 230 ofthe plate-like member 200, more preferably at least about 2 inches abovethe upper surface 230 of the plate-like member 200, and even morepreferably at least about 2.5 inches above the upper surface 230 of theplate-like member 200. In this embodiment, the first upturned surface410 intersects the plate-like member along a line that is generallyparallel to either the port side 123 of the hull 120 or the starboardside 124 of the hull 120. The second upturned surface 420 is positionedbetween the first upturned surface 410 and the first downturned surface310 and intersects the plate-like member along a line that is orientedat an oblique angle δ with respect to the pivot axis 210. The angle δpreferably is between about 60° to about 90°, and more preferably isabout 75°.

A third downturned surface 330 between the second downturned surface 320and the pivot axis 210 can further improve the wake on the surf-side. Anangle ε between the third downturned surface 330 and the lower surface220 of the central portion of the plate-like member 200 preferably isbetween about 30° to about 150°, and more preferably is about 90°. Theinventors believe this third downturned surface 330 further delays thewater on the non-surf side from converging with the water on the surfside. In the embodiment shown, the third downturned surface 330 ispositioned along the inboard portion I of the plate-like member 200 andintersects the plate-like member 200 along a line that is generallyperpendicular to the pivot axis 210. The third downturned surface 330preferably is at an inboard edge of the plate-like member, but it may beinward of the edge. Similar to the other downturned surfaces 310, 320,the third downturned surface 330 should extend far enough in a downwarddirection to delay or redirect the water. As with the other downturnedsurfaces 310, 320, the third downturned surface 330 is preferably shortenough that the third downturned surface 330 does not interact (or atleast minimizes interaction) with the water when in the non-deployedposition. The third downturned surface 330 preferably extends betweenabout ½ inch to about 3 inches below the lower surface 220 of theplate-like member 200, and more preferably extends about 1 inch belowthe lower surface 220 of the plate-like member 200.

The boat 100 of this embodiment uses a left-handed propeller 170, whichcauses the prop wash to be offset towards the starboard side. To balancethe desirability of the surf wakes on both sides of the boat 100, theport wake-modifying device 111 of this embodiment provides more delay ofthe water than does the starboard wake-modifying device 112. In thisembodiment, the port wake-modifying device 111 has the third downturnedsurface 330 while the starboard wake-modifying device 112 does not.However, the third downturned surface 330 may be provided on either theport or starboard wake-modifying device 111, 112, both, or neither.

FIG. 16 shows the port wake-modifying device 111 in a non-deployedposition, and FIG. 17 shows the port wake-modifying device 111 in adeployed position. Similarly, FIG. 28 shows the starboard wake-modifyingdevice 112 in a non-deployed position, and FIG. 29 shows the starboardwake-modifying device 112 in a deployed position. As water recovers fromunder the boat, it travels at an upward angle. The angle of waterrecovery will depend on a number of factors including hull design andoperational parameters, for example, speed. In the non-deployedposition, the wake-modifying device 111, 112 preferably is at an upwardangle so that it does not interact with the recovering water. Thewake-modifying device 111, 112 is moved from the non-deployed positionto a deployed position by pivoting about the pivot axis 210. In thedeployed position, the trailing portion T of the wake-modifying device111, 112 is lower than it is in the non-deployed position. The deployedposition preferably is even with the bottom of the hull and morepreferably extends at a downward angle ζ as shown in FIGS. 17 and 29. Asdiscussed above, the wake-modifying device 111, 112 may be pivotableabout an axis that is not horizontal, for example, it may be at an angleparallel to the deadrise. The deployed position is not limited to asingle angle ζ but rather may vary depending upon the preferences of thewater sports performer. In this embodiment, the angle ζ is directlyproportional to the size of the wake, but as the angle ζ gets larger,the wake begins to break (curl over) closer to the boat 100, reducingthe area on the wake that is desirable for surfing. In this embodiment,the angle ζ preferably is between about 0° and about 12°.

In the embodiment shown, a linear actuator 510 is used to move thewake-modifying device 111, 112 between the deployed and non-deployedpositions. The linear actuator 510 preferably is an electric linearactuator, such as one available from Lenco Marine. One end of the linearactuator 510 is screwed to the transom 122 of the boat 100. The otherend of the linear actuator is connected to a u-shaped bracket 202 by apin 204. The u-shaped bracket 202 is then bolted to the plate-likemember 200. Any suitable means may be used to move the wake-modifyingdevice 111, 112 between the deployed and non-deployed positions,including but not limited to hydraulic linear actuators and mechanicallevers.

The size of the wake-modifying device 111, 112 may be varied dependingupon the characteristics of the boat 100 and the desired wake. The liftprovided by the wake-modifying device 111, 112 is generally proportionalto the angles α, β, the surface area of the first and second downturnedsurfaces 310, 320, and the surface area of the plate-like member 200. Inthis embodiment, the wake-modifying device 111, 112 is about 17 incheslong and about 14.5 inches wide. Preferably, the wake-modifying device111, 112 is at least about 10 inches long and at least about 9 incheswide.

Because the wake-modifying device 111, 112 is used in a marineenvironment, it preferably is made of materials suitable for thatenvironment. In this embodiment, these materials are primarilycorrosion-resistant metal alloys such as stainless steel. Thewake-modifying device 111, 112, including the plate-like member 200,preferably should not deform during operation. Preferably, thewake-modifying device 111, 112 will have sufficient rigidity to maintainits shape at all speeds and especially at speeds suitable for surfing(approximately 9 mph to 12 mph). In the preferred embodiment, thewake-modifying device 111, 112 is made from 12 gauge stainless steelplate. Other suitable materials may be used instead, such as wood,plastic, fiber reinforced composites, or other metals includingaluminum.

FIGS. 18 and 30 show manufacturing views of the port and starboardwake-modifying devices 111, 112, respectively. The wake-modifying device111, 112 may be manufactured by cutting the device from a single platestock to the desired shape and then bending the downturned and upturnedsurfaces to the desired angles. In this embodiment, the plate-likemember 200, the downturned surfaces 310, 320, 330, and the upturnedsurfaces 410, 420 are an integral piece. Alternatively, some or all ofthe downturned and upturned surfaces may be formed as separate piecesand then attached to the plate-like member using any suitable joiningmethod such as welding, bolting, riveting, or the like.

Second Embodiment

Boat design plays an important role in establishing the wake shape.Design factors include, for example, the hull design and the weight ofthe boat. The wake-modifying device 111, 112 preferably is customizedbased on the boat design in order to produce the desired wake.

As an example of how hull design affects the boat's wake, a first boathaving a steeper deadrise than a second boat will typically allow thewater to recover closer to the transom of the boat. The shape of thecorners between the sides of the hull and the transom also impact therecovery of the water. A boat with smooth corners (e.g., having aradius) will allow the water to recover faster than will a boat withsquare corners. The wake-modifying devices 111, 112 of the secondembodiment are designed to provide greater lift to the boat on thenon-surf side and further delay and direct the water on the non-surfside.

FIG. 31 shows a stern view of a boat 100 equipped with wake-modifyingdevices 111, 112 according to a second preferred embodiment of theinvention. The port wake-modifying device 111 of the second embodimentis shown in FIGS. 32-45. The starboard wake-modifying device 112 of thesecond embodiment is shown in FIGS. 46-57.

As with the first embodiment, the port and starboard wake-modifyingdevices 111, 112 of the second embodiment are not symmetrical with oneanother. Here, the port wake-modifying device 111 includes two fins 340,350 attached to the lower surface 220 of the plate-like member 200.These fins 340, 350 extend at a downward angle η relative to the lowersurface 220 of the plate-like member 200. The downward angle ηpreferably is between about 30° and about 150°, and more preferably isabout 90°. The fins 340, 350 intersect the plate-like member 200 alonglines that are oriented at an angle θ relative to the pivot axis 210.This angle θ preferably is between about 15° and about 75°, and morepreferably is between about 30° and about 60°. In the embodiment shown,the fins 340, 350 are parallel to each other and at an angle θ of60°relative to the pivot axis 210. The inventors believe these fins 340,350 redirect the water outboard, further shifting the point ofconvergence aft from the transom 122 and toward the non-surf side. Aswith the downturned surfaces 310, 320, 330 and the upturned surfaces410, 420, the fins 340, 350 should extend far enough away from theplate-like member 200 to redirect the water flow. The fins 340, 350preferably should extend at least about 1 inch below the lower surface220 of the plate-like member 200, and more preferably should extend atleast about 2 inches below the lower surface 220 of the plate-likemember 200. In the embodiment shown, the fins 340, 350 have differentlengths. The fins preferably are about 4 inches to about 16 inches long,and more preferably are about 8 inches to about 12 inches long. The finspreferably do not extend beyond the edges of the plate-like member.

In the second embodiment, the third downturned surface 330 intersectsthe plate-like member along a line that is oriented at an oblique angleϕ relative to the pivot axis 210. The angle ϕ preferably is betweenabout 45° to about 90°, and more preferably is about 70°. All three ofthe downturned surfaces 310, 320, 330 form an angle α, ε with respect tothe lower surface 220 of the central portion of the plate-like member200 of about 135°. The wake-modifying devices 111, 112 of thisembodiment preferably are about 17 inches wide and about 16 and ½ incheslong.

Third Embodiment

The port and starboard wake-modifying devices 111, 112 in the previoustwo embodiments are asymmetrical with each other, but the wake-modifyingdevices 111, 112 can be symmetrical. Symmetrical wake-modifying devices111, 112 may be used, for example, with heavy boats where the propeller170 has less of an impact on the boat's wake. The third preferredembodiment shown in FIGS. 58-84 is an example of a symmetrical pair ofwake-modifying devices 111, 112. FIG. 58 shows a stern view of a boat100 equipped with wake-modifying devices 111, 112 according to a thirdembodiment of the invention. The port wake-modifying device 111 of thethird embodiment is shown in FIGS. 59-72. The starboard wake-modifyingdevice 112 of the third embodiment is shown in FIGS. 73-84. In thisembodiment, both the port and starboard wake-modifying devices 111, 112have two fins 340, 350. In the embodiment shown, the fins 340, 350 areparallel to each other and oriented at an angle θ of 45° relative to thepivot axis 210.

Control System

Those skilled in the art understand that the weight and displacement ofthe boat has a significant impact on the size and shape of the wake. Asa result, many recreational sport boats that are used for wakeboardingand wake surfing accommodate additional weight or ballast. Inparticular, many boats are designed to have ballast added to the surfside of the boat to increase the displacement of that side of the boat.This weight may be added by any number of ways known to those skilled inthe art. One way is to position more people on the surf side of the boatthan on the non-surf side. Another way is to add ballast through the useof ballast bags or ballast sacks. Yet another way to add weight isthrough ballast tanks installed in the boat. Preferably, two ballasttanks are positioned in the stern of the boat near the bottom of thehull, one on each side of the boat, and a third ballast tank ispositioned along the boat's centerline near the bottom of the hull,forward of the two rear ballast tanks. If ballast bags are used inaddition to ballast tanks, the ballast bags may be plumbed into theballast system of the boat. Both the ballast tanks and the ballast bagsoperate similarly in that water may be pumped into the tank or bag byballast pumps to add weight. In some boats, both ballast tanks andballast bags may be used simultaneously. For example, all three ballasttanks may be filled to increase the displacement of the stern of theboat, and a ballast bag on the surf side of the boat may be filled tofurther increase the displacement on the surf side.

A control system is used to operate the wake-modifying devices 111, 112.When the wake-modifying devices 111, 112 are used with plumbed-inballast, the control system preferably controls both the ballast and thewake-modifying devices 111, 112. This control system preferably includesa controller that controls the linear actuators 510 and the ballastpumps. The controller may be any suitable controller known in the artincluding a controller comprising a CPU, ROM, and RAM. The controlsystem also includes an input device. In the preferred embodiment, theinput device is a touch screen located at the control console 140 of theboat 100. Also in this embodiment, the controller is co-located with thetouch screen. Those skilled in the art will recognize that any suitableinput device including buttons, switches, dials, or the like may beused.

An exemplary touch screen 610 is shown in FIG. 85. This touch screen 610is shown in a manual mode. In this mode, a user can manually adjust theamount of water in the ballast tanks and manually adjust the percentageof deployment of the wake-modifying devices 111, 112. To adjust ballast,the user selects the “BALLAST” button 611. To adjust the deployment ofthe wake-modifying devices or center trim tab, the user selects the“TABS” button 612. To adjust the speed of the boat, the user selects the“SET SPEED” button 613. When one of these buttons is selected, a newscreen is displayed that allows the user to adjust the selectedparameter. When the user selects the “TABS” button 612, for example, an“EDIT TABS” screen 620 is displayed as shown in FIG. 86. On this screen620, the user may adjust the percentage deployment of the wake-modifyingdevices 111, 112 and/or the center trim tab 20. To deploy the portwake-modifying device 111, for example, a user swipes his or her fingerin direction A in the area 621 until the desired percentage deployment(50 percent in the example shown) is reached. Alternatively, the usermay use adjustment arrows 622 to incrementally change the percentagedeployment. When the percentage deployment of the port wake-modifyingdevice 111 is changed, the controller drives the linear actuator 510 ofthe port wake-modifying device 111 to move the port wake-modifyingdevice 111 to the set position. The starboard wake-modifying device 112and the center trim tab 20 are adjusted in the same manner.

As another option, the wake-modifying devices, ballast, and boat speedmay be controlled using user-defined programmed settings. A user canmanually set each of the parameters in the manual mode as describedabove and then save these settings as a user-defined profile. Inoperation, a touch location 610, shown in FIG. 85, may be used to togglebetween these user-defined programmed settings. In this embodiment, auser toggles between settings by swiping touch position 614 to the leftor right.

In addition to or instead of the foregoing, the control system caninclude preprogrammed settings established by the boat manufacturer.After one of the preprogrammed settings has been selected by a user, acruise control screen 630 may be displayed, such as shown in FIG. 87.The boat may be set to cruise at a specific speed by selecting the “ON”button 632. If the user desires to switch between preprogrammedsettings, the user may select the “SWITCH” button 631. Selecting the“SWITCH” button 631 causes a pop-up window to be displayed within thecontrol screen 640, such as shown in FIG. 88. Using the pop-up windowthe user may select a different preprogrammed setting. In thisembodiment, four preprogrammed settings are shown. The two “mellow”settings (“SURF LEFT MELLOW” 641 and “SURF RIGHT MELLOW” 643) may beprogrammed such that the controller drives the linear actuator 510 todeploy the wake-modifying device 111, 112 on the non-surf side to arelatively shallow deployed position. The two “steep” settings (“SURFLEFT STEEP” 642 and “SURF RIGHT STEEP” 644) may be programmed tomaximize the size of the wake. In these “steep” settings, the controllerdrives the linear actuator 510 to deploy the wake-modifying device 111,112 on the non-surf side to the maximum deployed position. In additionto or instead of a touch screen, other known input devices, such asstatic buttons 650, can be used.

The embodiments described and shown herein are examples of preferredembodiments of the present invention and are provided for illustrativepurposes only. They are not intended to limit the scope of theinvention. Although specific configurations, structures, materials, etc.have been shown and described, such are not limiting. Modifications andvariations are contemplated within the scope of the invention, which isto be limited only by the scope of the claims.

What is claimed is:
 1. A wake-modifying device configured to generate asurf wake behind a boat, the wake-modifying device comprising: aplate-like member adapted to be pivotally mounted aft of a transom ofthe boat on either a port side of the boat's centerline or a starboardside of the boat's centerline; and at least two downturned surfaces at atrailing portion of the plate-like member, the two downturned surfacesbeing at an obtuse angle relative to each other.
 2. The wake-modifyingdevice of claim 1, wherein at least one of the downturned surfaces is ata trailing edge of the plate-like member.
 3. The wake-modifying deviceof claim 1, wherein an angle between at least one of the downturnedsurfaces and a lower surface of a central portion of the plate-likemember is between about 120° to about 135°.
 4. The wake-modifying deviceof claim 1, wherein the obtuse angle is between about 135° to about150°.
 5. The wake-modifying device of claim 1, further comprising atleast one upturned surface at an outboard portion of the plate-likemember.
 6. The wake-modifying device of claim 1, further comprising atleast one fin attached to a lower surface of the plate-like member.
 7. Awake-modifying device configured to generate a surf wake behind a boat,the wake-modifying device comprising: a plate-like member adapted to bepivotally mounted aft of a transom of the boat on either a port side ofthe boat's centerline or a starboard side of the boat's centerline; afirst downturned surface at an inboard portion of the plate-like member,the first downturned surface lying in a first plane; and a seconddownturned surface located entirely within a trailing portion of theplate-like member, the second downturned surface lying in a second planewhich intersects the first plane.
 8. The wake-modifying device of claim7, wherein the second downturned surface is at a trailing edge of theplate-like member.
 9. The wake-modifying device of claim 7, wherein thefirst downturned surface is at a trailing portion of the plate-likemember.
 10. The wake-modifying device of claim 7, wherein the firstplane intersects a leading edge of the plate-like member.
 11. Thewake-modifying device of claim 7, wherein the second plane issubstantially parallel to a leading edge of the plate-like member. 12.The wake-modifying device of claim 7, wherein the second plane issubstantially perpendicular to the first plane.
 13. The wake-modifyingdevice of claim 7, wherein an angle between at least one of first andsecond downturned surface and a lower surface of a central portion ofthe plate-like member is between about 120° to about 135°.
 14. Thewake-modifying device of claim 7, further comprising at least oneupturned surface at an outboard portion of the plate-like member. 15.The wake-modifying device of claim 7, further comprising at least onefin attached to a lower surface of the plate-like member.
 16. Awake-modifying device configured to generate a surf wake behind a boat,the wake-modifying device comprising: a plate-like member adapted to bepivotally mounted aft of a transom of the boat on either a port side ofthe boat's centerline or a starboard side of the boat's centerline; atleast one downturned surface at a trailing portion of the plate-likemember; and a fin attached to a lower surface of the plate-like member,the fin being angled obliquely relative to a leading edge of theplate-like member.
 17. The wake-modifying device of claim 16, whereinthe fin is angled between about 15° and about 75° relative to theleading edge of the plate-like member.
 18. The wake-modifying device ofclaim 16, wherein an angle between the fin and a lower surface of acentral portion of the plate-like member is about 90°.
 19. Thewake-modifying device of claim 16, wherein the at least onewake-modifying device includes at least two fins attached to the lowersurface of the plate-like member, and the fins are parallel to eachother.
 20. The wake-modifying device of claim 16, further comprising atleast one upturned surface at an outboard portion of the plate-likemember.